Elastomeric Liquid Membrane

Brands, application and use cases

On products, we work primarily with four established brands in the Quebec market: Resisto, Soprema, Bakor and Blue Seal. Resisto is probably the most common brand in residential work: their range of liquid elastomeric membranes — generally based on SBS-modified bitumen and polymers — applies by roller or sprayer, dries in a few hours, and finishes in a clean matte black. Soprema, a major Quebec-based manufacturer, makes high-performance liquid membranes — often polyurethane-based — used in both commercial and high-end residential work; their strength is UV durability and tolerance to structural movement. Bakor (now Henry/Bakor) is a long-standing reference for modified bituminous coatings, still very much used in combined goudronnage-plus-drainage-membrane applications. Blue Seal is a more affordable Quebec product, a fit for budget renovations where 12-to-18-year service life is acceptable rather than 25. The choice between these brands depends on substrate (poured concrete or block), expected exposure (high water table or not), budget and warranty requirements — our diagnosis points you to the right product.

Application is either by roller or by airless spray. A long-nap roller (15 to 20 mm) is still the right tool on small surfaces, targeted touch-ups, and projects where overspray would be a problem — for example near a parked car or fragile exterior cladding. It gives excellent thickness control and fills the concrete pores well. Airless spray application comes into its own on long perimeters, foundations with complex geometry, and larger projects: the atomized spray reaches every corner, thickness stays uniform throughout, and the speed allows two crossed coats in a single working day. On a typical renovation we apply two coats of about 1.5 mm each (dry thickness), for a total 3 mm of continuous rubber membrane. Between coats we respect the manufacturer's cure time — usually four to six hours at 20 °C. On a new foundation, the membrane is then protected by a Delta-MS dimpled membrane or by a rigid insulation panel before backfilling, to prevent angular stones from damaging the fresh coating.

There are four use cases where elastomeric liquid membrane really shines. First, irregular shapes: re-entrant angles, rounded corners, multiple pipe penetrations, stepped foundations on sloped lots. A prefabricated sheet membrane requires cuts, heat-welded joints and seam work at every detail — each one a potential weak point. Liquid membrane follows the geometry perfectly, with zero seams. Second, renovations with partial excavation: when only certain sections of the perimeter are accessible because of mature landscaping, an attached outbuilding or a deck. Liquid membrane ties cleanly into existing sections and allows a surgical intervention. Third, restricted access: narrow trenches, limited overhead clearance (for example under a balcony), zones where you cannot unroll a one-metre-wide sheet membrane. An airless sprayer reaches spaces a roller cannot. Fourth, concrete-block foundations with tired mortar joints: the rubber membrane wraps the joints and delivers a tightness that a simple tar coating could not.

Compared to Delta-MS membrane, the fundamental difference is the function. Delta-MS is a dimpled polyethylene sheet that creates a drainage space between the wall and the soil — water flows in those cavities all the way down to the French drain, never touching the concrete. Service life is 25-plus years and it is our default on new builds. Elastomeric liquid membrane does not create a drainage space: it is a continuous film bonded to the concrete, stopping water where it shows up. Service life is 15 to 25 years depending on the product and soil conditions. On an ideal job, the two combine — elastomeric on the concrete as the first barrier, Delta-MS over it as the drainage layer. On renovations where full excavation is awkward, elastomeric on its own still earns its place because it goes on fast, adapts to every geometry and ties cleanly into already-treated sections. Our job is to explain plainly where each method ends and where the other begins. Written workmanship warranty, current RBQ, APCHQ, RECQ, Réno-Maître and Delta-MS certifications, and a local team based in Saint-Paul for more than 30 years.